The present invention relates to an image analyzing apparatus and, particularly, to such an apparatus which can quantitatively analyze images in a desired manner.
Various image analyzing methods are known. These include an autoradiographic process comprising the steps of introducing a radioactively labeled substance into an organism, using the organism or a part of the tissue of the organism as a specimen, placing the specimen and a radiographic film such as a high sensitivity type X-ray film together in layers for a certain period of time to expose the radiographic film thereto and obtaining locational information on the radioactively labeled substance in the specimen from the resolved pattern of the radiographic film, a chemiluminescent process comprising the steps of selectively labeling a fixed high molecular substance such as a protein or a nucleic acid sequence with a labeling substance which generates chemiluminescent emission when it contacts a chemiluminescent substance, contacting the high molecular substance selectively labeled with the labeling substance and the chemiluminescent substance, detecting the chemiluminescent emission in the wavelength of visible light generated by the contact of the chemiluminescent substance and the labeling substance and obtaining information relating to the high molecular substance such as genetic information, a detecting method using an electron microscope comprising the steps of irradiating a metal or nonmetal specimen with an electron beam, detecting a diffraction image, transmission image or the like and effecting elemental analysis, composition analysis of the specimen, structural analysis of the specimen or the like, or irradiating the tissue of an organism with an electron beam and detecting an image of the tissue of the organism, and a radiographic diffraction image detecting process comprising the steps of irradiating a specimen with radiation, detecting a radiographic diffraction image and effecting structural analysis of the specimen or the like.
Conventionally, these methods are carried out by employing a photographic film as a detecting material, recording a radiographic image, a chemiluminescent image, an electron microscopic image, a radiographic diffraction image or the like on the photographic film and observing a visual image with the eyes. However, in the case where a photographic film is employed as a detecting material, since a radiographic film has low sensitivity, there is a problem that it takes considerable time for recording an image in the autoradiographic process and the radiographic diffraction image detecting process. Further, in the chemiluminescent process, although it is necessary to employ a highly sensitive film having a high gamma value for detecting very weak chemiluminescent emission, when the highly sensitive film having a high gamma value is employed, it is difficult to expose the film reliably using a straight portion of the characteristic curve. Therefore, the film is often exposed improperly and it is necessary to repeatedly expose the films under various exposure conditions. Moreover, in the detecting process using the electron microscope, since the straight portion of the characteristic curve of a photographic film for an electron microscope is short, it is difficult to determine the proper exposure condition and it is necessary to repeatedly expose the films. Furthermore, in either processes, it is indispensable to chemically develop the films and, therefore, the operations are unavoidably complicated.
In view of the above, there have been proposed an autoradiographic process, a chemiluminescent process, a detecting process using an electron microscope and a radiographic diffraction image detecting process comprising the steps of employing, as a detecting material for the radiation, the visible light, the electron beam or the like, not a photographic film, but a stimulable phosphor which can absorb and store the energy of radiation, visible light, an electron beam or the like upon being irradiated therewith and release a stimulated emission whose amount is proportional to that of the received radiation, the visible light, the electron beam or the like upon being stimulated with an electromagnetic wave having a specific wavelength range, photoelectrically detecting the stimulated emission released from the stimulable phosphor, converting the detection signal to a digital signal, effecting a predetermined image processing on the obtained image data and reproducing an image on displaying means such as a CRT or the like or a photographic film (See for example, Japanese Patent Publication No. 1-60784, Japanese Patent Publication No. 1-60782, Japanese Patent Publication No. 4-3952, U.S. Pat. No. 5,028,793, UK Patent Application 2,246,197 A, Japanese Patent Application Laid Open No. 61-51738, Japanese Patent Application Laid Open No. 61-93538, Japanese Patent Application Laid Open No. 59-15843 and the like).
According to the detecting processes using the stimulable phosphor, development, which is a chemical processing, becomes unnecessary. In addition, the exposure time can be markedly shortened in the autoradiographic process and the radiographic diffraction image detecting process. Improper exposure becomes rare and the exposing operation becomes easy in the chemiluminescent process and the detecting process using the electron microscope. Further, since the image is reproduced after the detected signal has been converted to a digital signal, the image can be reproduced in a desired manner by effecting signal processing on image data and it is also possible to effect quantitative analysis using a computer. Use of a stimulable phosphor in these process is therefore advantageous.
In the autoradiographic process, the chemiluminescent process and the detecting process using the electron microscope and the radiographic diffraction image detecting process, it is often required for quantitatively analyzing images to specify a particular image area and add up the density of the pixels in the image area.
In the case where the quantitative analysis is effected using display means such as a CRT, only a density equal to or higher than a predetermined value can be specified in conventional image analyzing apparatuses and, therefore, if there is an image area whose density is higher than that of the image area to be quantitatively analyzed in the image, it is impossible to specify a desired image area and quantitatively analyze the image area.
The same problems occur in the case where, after an autoradiographic image, a chemiluminescent image, an electron microscopic image, a radiographic diffraction image or the like was recorded on a photographic film, the recorded image is photoelectrically read and converted to a digital signal and the thus obtained image signal is signal processed in a desired manner, thereby reproducing a visible image on displaying means such as a CRT or the like or a photographic film.
It is therefore an object of the present invention to provide an image analyzing apparatus for forming images on display means such as a CRT based on image data and quantitatively analyzing the images, which can specify a desired image area and quantitatively analyze the image area.
The above and other objects of the present invention can be accomplished by an image analyzing apparatus for forming images on display means based on image data and effecting quantitative analysis comprising image density lower limit setting means for setting a lower limit value of image density, image density upper limit setting means for setting an upper limit value of image density and image area specifying means for specifying image areas having density equal to or higher than the lower limit value of image density set by the image density lower limit setting means and equal to or lower than the upper limit value of image density set by the image density upper limit setting means from among the images displayed on the display means.
In a preferred aspect of the present invention, the image analyzing apparatus further comprises image area outline specifying means for specifying an outline of the image area to be quantitatively analyzed and the image area specifying means is adapted to specify an image area having density equal to or higher than the lower limit value of image density set by the image density lower limit setting means and equal to or lower than the upper limit value of image density set by the image density upper limit setting means in the image contained in the image area within the outline specified by the image area outline specifying means.
In a further preferred aspect of the present invention, the image analyzing apparatus further comprises image data storing means for storing image data and memory means for two-dimensionally mapping and temporarily storing the image data stored in the image data storing means and the image area specifying means is adapted to data-process the image data within an image data area corresponding to an image area specified thereby and stored in the memory means so that the image area can be displayed on the display means with predetermined density.
In a further preferred aspect of the present invention, the image analyzing apparatus further comprises graphic data storing means for storing graphic data corresponding to patterns to be displayed on the display means and the image area outline specifying means is adapted to specify the outline of the image area to be analyzed based on the graphic data stored in the graphic data storing means.
In a further preferred aspect of the present invention, the memory means comprises temporary memory means for two-dimensionally mapping and temporarily storing image data stored in the image data storing means, selected image data memory means for two-dimensionally mapping and temporarily storing a part of the image data stored in the temporary memory means and enlarged, reduced or unchanged in scale, synthesized data memory means for two-dimensionally mapping and temporarily storing data obtained by synthesizing the image data stored in the selected image data memory means and graphic data stored in the graphic data storing means and window memory means for two-dimensionally mapping and temporarily storing a part of the image data stored in the synthesized data memory means, and the image analyzing apparatus further comprises image data selecting means for selecting a part of the image data stored in the temporary memory means, image data enlarging/reducing means for enlarging or reducing the image data selected by the image data selecting means, data synthesizing means for synthesizing the image data stored in the selected image data memory means and graphic data stored in the graphic data storing means and two-dimensionally mapping and temporarily storing them in the synthesized data memory means and data area selecting means for selecting a part of the areas of the image data and the graphic data stored in the synthesized data memory means and two-dimensionally mapping and temporarily storing said part in the window memory means, and the image area specifying means is adapted to data-process the image data stored in the window memory means so as to specify image areas having density equal to or higher than the lower limit value of image density set by the image density lower limit setting means and equal to or lower than the upper limit value of image density set by the image density upper limit setting means from among the images displayed on the display means.
In a further preferred aspect of the present invention, the image data are produced using a stimulable phosphor sheet.
In a further preferred aspect of the present invention, the image data are constituted by image data selected from a group consisting of autoradiographic image data, radiographic diffraction image data, electron microscopic image data and chemiluminescent image data.
In a still further preferred aspect of the present invention, the autoradiographic image data, the radiographic diffraction image data and the electron microscopic image data are produced by absorbing and storing the energy of a radiation or an electron beam emitted from a specimen in a stimulable phosphor, irradiating the stimulable phosphor with an electromagnetic wave and photoelectrically converting light emitted from the stimulable phosphor.
In a further preferred aspect of the present invention, the chemiluminescent image data are produced by absorbing and storing the energy of a visible light emitted from a specimen in a stimulable phosphor, irradiating the stimulable phosphor with an electromagnetic wave and photoelectrically converting light emitted from the stimulable phosphor.
In the present invention, the stimulable phosphor employed for producing an autoradiographic image, a radiographic diffraction image and an electron microscopic image may be of any type insofar as it can store radiation energy or electron beam energy and can be stimulated by an electromagnetic wave to release the radiation energy or electron beam energy stored therein in the form of light. However, a stimulable phosphor which can be stimulated by light having a visible light wavelength is preferably employed. More specifically, preferably employed stimulable phosphors include alkaline earth metal fluorohalide phosphors (Ba1xe2x88x92x,M2+x)FX:yA (where M2+ is at least one alkaline earth metal selected from the group consisting of Mg, Ca, Sr, Zn and Cd; X is at least one halogen selected from the group consisting of Cl, Br and I, A is at least one element selected from the group consisting of Eu, Tb, Ce, Tm, Dy, Pr, He, Nd, Yb and Er; x is equal to or greater than 0 and equal to or less than 0.6 and y is equal to or greater than 0 and equal to or less than 0.2.) disclosed in U.S. Pat. No. 4,239,968, alkaline earth metal fluorohalide phosphors SrFX:Z (where X is at least one halogen selected from the group consisting of Cl, Br and I; and Z is at least one of Eu and Ce.) disclosed in Japanese Patent Application Laid Open No. 2-276997, europium activated complex halide phosphors BaFX.xNaXxe2x80x2:aEu2+ (where each of X or Xxe2x80x2 is at least one halogen selected from the group consisting of Cl, Br and I; x is greater than 0 and equal to or less than 2; and y is greater than 0 and equal to or less than 0.2.) disclosed in Japanese Patent Application Laid Open No. 589-56479, cerium activated trivalent metal oxyhalide phosphors MOX:xCe (where M is at least one trivalent metal selected from the group consisting of Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb and Bi; X is at least one halogen selected from the group consisting of Br and I; and x is greater than 0 and less than 0.1.) disclosed in Japanese Patent Application Laid Open No. 58-69281, cerium activated rare earth oxyhalide phosphors LnOX:xCe (where Ln is at least one rare earth element selected from the group consisting of Y, La, Gd and Lu; X is at least one halogen selected from the group consisting of Cl, Br, and I; and x is greater than 0 and equal to or less than 0.1.) disclosed in U.S. Pat. No. 4,539,137 and europium activated complex halide phosphors MIIFX.aMIXxe2x80x2.bMxe2x80x2IIXxe2x80x32.cMIIIXxe2x80x3xe2x80x23.xA:yEu2+ (where MII is at least one alkaline earth metal selected from the group consisting of Ba, Sr and Ca; MI is at least one alkaline metal selected from the group consisting of Li, Na, K, Rb and Cs; Mxe2x80x2II is at least one divalent metal selected from the group consisting of Be and Mg; MIII is at least one trivalent metal selected from the group consisting of Al, Ga, In and Tl; A is at least one metal oxide; X is at least one halogen selected from the group consisting of Cl, Br and I; each of Xxe2x80x2, Xxe2x80x3 and Xxe2x80x3xe2x80x2 is at least one halogen selected from the group consisting of F, Cl, Br and I; a is equal to or greater than 0 and equal to or less than 2; b is equal to or greater than 0 and equal to or less than 10xe2x88x922; c is equal to or greater than 0 and equal to or less than 10xe2x88x922; a+b+c is equal to or greater than 10xe2x88x922; x is greater than 0 and equal to or less than 0.5; and y is greater than 0 and equal to or less than 0.2.) disclosed in U.S. Pat. No. 4,962,047.
In the present invention, the stimulable phosphor employed for producing a chemiluminescent image may be of any type insofar as it can store the energy of light having a visible light wavelength and can be stimulated by an electromagnetic wave to release the energy of light having a visible light wavelength stored therein in the form of light. However, a stimulable phosphor which can be stimulated by light having a visible light wavelength is preferably employed. More specifically, preferably employed stimulable phosphors include metal halophosphates, rare-earth-activated phosphors, aluminate-host phosphors, silicate-host phosphors and fluoride-host phosphors disclosed in UK Patent Application 2,246,197 A.
The above and other objects and features of the present invention will become apparent from the following description made with reference to the accompanying drawings.